The present invention relates to metal compounds of the formula I, 
where the variables are defined as follows:
M is selected from among Ni and Pd in the oxidation state +II;
Nu1, Nu2 are selected independently from among N, P and As,
E is selected from among 
and
E1, E2, E3 and E4 are selected independently from among C, Si and Ge;
R1 to R12 are selected independently from among
hydrogen,
C1-C8-alkyl, substituted or unsubstituted,
C2-C8-alkenyl, substituted or unsubstituted, having from one to 4 isolated or conjugated double bonds;
C3-C12-cycloalkyl, substituted or unsubstituted,
C7-C13-aralkyl,
C6-C14-aryl, unsubstituted or monosubstituted or polysubstituted by identical or different substituents selected from among
C1-C8-alkyl, substituted or unsubstituted,
C3-C12-cycloalkyl,
C7-C13-aralkyl,
C6-C14-aryl,
halogen,
C1-C6-alkoxy, substituted or unsubstituted,
C6-C14-aryloxy,
SiR18R19R20 and Oxe2x80x94SiR18R19R20, where R18-R20 are selected from among hydrogen, C1-C8-alkyl, C3-C12-cycloalkyl, C7-C13-aralkyl and C6-C14-aryl;
five- to six-membered nitrogen-containing heteroaryl radicals, unsubstituted or monosubstituted or polysubstituted by identical or different substituents selected from among
C1-C8-alkyl, substituted or unsubstituted,
C3-C12-cycloalkyl,
C7-C13-aralkyl,
C6-C14-aryl,
halogen,
C1-C6-alkoxy,
C6-C14-aryloxy,
SiR18R19R20 and Oxe2x80x94SiR18R19R20, where R18-R20 are selected from among hydrogen, C1-C8-alkyl, C3-C12-cycloalkyl, C7-C13-aralkyl and C6-C14-aryl;
where adjacent radicals R1 to R10 together with E may be joined to form a saturated or olefinically unsaturated 5- to 12-membered ring;
A1, A3 are selected from among Cxe2x80x94R15, Cxe2x80x94R16, Sixe2x80x94R15, Sixe2x80x94R16 and N,
A2 is selected from among Cxe2x80x94R17, Sixe2x80x94R17 and N,
where not more than one Aj is a nitrogen atom and j=1, 2, 3;
R13 to R17 are selected from among
hydrogen,
C1-C8-alkyl, substituted or unsubstituted,
C2-C8-alkenyl, substituted or unsubstituted, having from one to 4 isolated or conjugated double bonds;
C3-C12-cycloalkyl, substituted or unsubstituted,
C7-C13-aralkyl,
C6-C14-aryl, unsubstituted or monosubstituted or polysubstituted by identical or different substituents selected from among
C1-C8-alkyl, substituted or unsubstituted,
C3-C12-cycloalkyl,
C7-C13-aralkyl,
C6-C14-aryl,
halogen,
C1-C6-alkoxy,
C6-C14-aryloxy,
SiR18R19R20 and Oxe2x80x94SiR18R19R20, where R18-R20 are selected from among hydrogen, C1-C8-alkyl, C3-C12-cycloalkyl, C7-C13-aralkyl and C6-C14-aryl;
five- to six-membered nitrogen-containing heteroaryl radicals, unsubstituted or monosubstituted or polysubstituted by identical or different substituents selected from among
C1-C8-alkyl, substituted or unsubstituted,
C3-C12-cycloalkyl,
C7-C13-aralkyl,
C6-C14-aryl,
halogen,
C1-C6-alkoxy,
C6-C14-aryloxy,
SiR18R19R20 and Oxe2x80x94SiR18R19R20, where R18-R20 are selected from among C1-C8-alkyl, C3-C12-cycloalkyl, C7-C13-aralkyl and C6-C14-aryl;
where R13 to R17 together with one or more atoms Aj may form a saturated or unsaturated 5- to 12-membered ring
and [Y]xe2x88x92 is an anion.
These metal compounds can be used for the polymerization and copolymerization of olefins. The present invention also provides a process for the polymerization and copolymerization of olefins using one or more of the metal compounds of the present invention. Furthermore, the present invention provides supported catalysts comprising one or more of the compounds of the present invention for the polymerization or copolymerization of olefins, a process for preparing the supported catalysts of the present invention and a process for the polymerization or copolymerization of olefins using a supported catalyst according to the present invention. Finally, the present invention provides a process for preparing the metal compounds of the present invention.
Polymers and copolymers of olefins are of great economic importance because the monomers are readily available in large quantities and because the polymers can be varied within a wide range by variation of the production process or the processing parameters. In the production process, the catalyst used is of particular significance. Apart from Ziegler-Natta catalysts, various single-site catalysts are of increasing importance. In these single-site catalysts, central atoms which have been examined in detail in recent times are not only Zr as in metallocene catalysts (H.-H. Brintzinger et al., Angew. Chem. 1995, 107, 1255) but also Ni or Pd (WO 96/23010) and Fe and Co (e.g. WO 98/27124). The complexes of Ni, Pd, Fe and Co are also referred to as complexes of late transition metals.
For industrial use, metallocene catalysts have disadvantages. The catalysts are very sensitive to impurities in the industrially available monomers, in the process gas and in the solvents used. Impurities which cause problems are, for example, moisture and oxygen as well as CO, but also Lewis bases in general, e.g. ethers. Furthermore, the price of Zr as central metal in the industrially important zirconocenes is very high.
While Ni or Pd complexes (WO 96/23010) catalyze the formation of highly branched, commercially less interesting polymers, the use of Fe or Co complexes leads to the formation of highly linear polyethylenes.
The abovementioned complexes are polymerization-inactive as such and have to be activated by means of cocatalysts. Cocatalysts used for the polymerization of ethylene are methylaluminoxane (xe2x80x9cMAOxe2x80x9d) or modified methylaluminoxane (xe2x80x9cMMAOxe2x80x9d)in which a certain percentage of the methyl groups have been replaced by isobutyl groups.
However, the use of MAO or other aluminoxanes has disadvantages:
MAO and other aluminoxanes have to be used in a large molar excess; from 100- to 1000-fold excesses are customary. The cocatalyst therefore becomes a significant cost factor for the catalysts.
Aluminoxanes are not molecular defined substances and their ability to activate transition metal complexes depends greatly on the method of preparation and impurities. Furthermore, the storage temperature and the storage time play a role. Quality control is difficult.
Aluminoxanes always have to be stored under refrigeration, because otherwise they tend to form gels. Aluminoxane gels are unsuitable as cocatalysts.
Aluminoxanes have to be used in a large excess and increase the residual ash content of the polymer.
Aluminoxanes are provided commercially as solutions, so that much otherwise worthless solvent has to be transported.
Aluminoxanes, particularly those having C1-C4-alkyl radicals, and their solutions are pyrophoric and require increased safety measures.
Another class of known cocatalysts is made up by strong Lewis acids and salts of noncoordinating or only weakly coordinating anions bearing bulky substituents. Suitable Lewis acids and salts are selected boron compounds bearing electron-withdrawing groups (e.g. trispentafluorophenylborane, N,N-dimethylanilinium tetrakispentafluorophenylborate, tri-n-butylammonium tetrakispentafluorophenylborate, N,N-dimethylanilinium tetrakis(3,5-bisperfluoromethyl)phenylborate, tri-n-butylammonium tetrakis(3,5-bisperfluoromethyl)phenylborate and tritylium tetrakispentafluorophenylborate, usually together with an aluminum alkyl. These activators are described in EP-A 0 468 537 and EP-A 0 426 638. A disadvantage of these catalyst systems is that they are air and moisture sensitive because of the use of aluminum alkyls. Other Lewis bases such as ethers also have to be carefully excluded, likewise CO and CO2.
Also known are palladium complexes of the formula A or B, 
(EP-A 0 827 515) where R, Rxe2x80x2, Rxe2x80x3 and Rxe2x80x2xe2x80x3 are selected from among various alkyl and aryl radicals, E is a bridging element, Nu1 and Nu2 are selected from among N, P and As, and [Z] is a counterion.
If the further ligands X1 and X2 on the Pd are selected from among halogen, aryl, aralkyl and alkyl and L1 is an uncharged ligand such as acetonitrile or diethyl ether, the complexes of the formulae A and B are suitable for preparing polyolefins and olefin copolymers, in particular with polar comonomers. However, the complexes of the formulae A and B have disadvantages in use:
If X1 and X2 are selected from among alkyl, aryl and aralkyl, the complexes are air and moisture sensitive and have a poor storage stability.
If X1 and X2 are each halide, the activity of the complexes is frequently too low for industrial applications.
When Lewis bases, air and moisture have to be carefully excluded, as required by the known catalyst systems, the monomers and suspension media and solvents in the polymerization have to meet particular purity requirements, which generally leads to high costs. Furthermore, the known catalysts have only a limited shelf life.
It is an object of the present invention to find a catalyst system which can be handled without a great outlay in terms of apparatus for exclusion of air and moisture and without purification of monomers, and which requires no activators. A further object is to polymerize and copolymerize olefins using this catalyst system.
We have found that these objects are achieved by the metal compounds defined at the outset.
In formula I,
M is Ni or Pd, preferably Ni;
Nu1 and Nu2 are identical or different and are selected from among N, P and As, preferably identical and selected from among N and P, particularly preferably both P;
the bridging element E is selected from among 
being preferred as bridging element.
E1, E2, E3 and E4 are selected independently from among C, Si and Ge, and are preferably C and Si and particularly preferably C.
R1 to R12 are selected independently from among
hydrogen,
C1-C8-alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, 1,2-dimethylpropyl, isoamyl, n-hexyl, isohexyl, sec-hexyl, n-heptyl, isoheptyl and n-octyl; preferably C1-C6-alkyl such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, 1,2-dimethylpropyl, isoamyl, n-hexyl, isohexyl, sec-hexyl, particularly preferably C1-C4-alkyl such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and
examples of substituted C1-C8-alkyl groups are: monohalogenated and polyhalogenated C1-C8-alkyl groups such as fluoromethyl, difluoromethyl, trifluoromethyl, chloromethyl, dichloromethyl, trichloromethyl, bromomethyl, dibromomethyl, tribromomethyl, pentafluoroethyl, perfluoropropyl and perfluorobutyl, particularly preferably fluoromethyl, difluoromethyl, trifluoromethyl and perfluorobutyl;
C2-C8-alkenyl having from one to 4 isolated or conjugated double bonds, for example vinyl, 1-allyl, 3-allyl, xcfx89-butenyl, xcfx89-pentenyl, xcfx89-hexenyl, 1-cis-buta-1,3-dienyl or 1-cis-hexa-1,5-dienyl;
examples of substituted C2-C8-alkenyl groups are: isopropenyl, 1-isoprenyl, xcex1-styryl, xcex2-styryl, 1-cis-1,2-phenylethenyl and 1-trans-1,2-phenylethenyl;
C3-C12-cycloalkyl such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, cycloundecyl and cyclododecyl; preferably cyclopentyl, cyclohexyl and cycloheptyl;
examples of substituted cycloalkyl groups are: 2-methylcyclopentyl, 3-methylcyclopentyl, cis-2,4-dimethylcyclopentyl, trans-2,4-dimethylcyclopentyl, cis-2,5-dimethylcyclopentyl, trans-2,5-dimethylcyclopentyl, 2,2,5,5-tetramethylcyclopentyl, 2-methylcyclohexyl, 3-methylcyclohexyl, 4-methylcyclohexyl, cis-2,6-dimethylcyclohexyl, trans-2,6-dimethylcyclohexyl, cis-2,6-diisopropylcyclohexyl, trans-2,6-diisopropylcyclohexyl, 2,2,6,6-tetramethylcyclohexyl, 2-methoxycyclopentyl, 2-methoxycyclohexyl, 3-methoxycyclopentyl, 3-methoxycyclohexyl, 2-chlorocyclopentyl, 3-chlorocyclopentyl, 2,4-dichlorocyclopentyl, 2,2,4,4-tetrachlorocyclopentyl, 2-chlorocyclohexyl, 3-chlorocyclohexyl, 4-chlorocyclohexyl, 2,5-dichlorocyclohexyl, 2,2,6,6-tetrachlorocyclohexyl, 2-thiomethylcyclopentyl, 2-thiomethylcyclohexyl, 3-thiomethylcyclopentyl, 3-thiomethylcyclohexyl and further derivatives;
C7-C13-aralkyl, preferably C7-C12-phenylalkyl such as benzyl, 1-phenethyl, 2-phenethyl, 1-phenylpropyl, 2-phenylpropyl, 3-phenylpropyl, neophyl (1-methyl-1-phenylethyl), 1-phenylbutyl, 2-phenylbutyl, 3-phenylbutyl and 4-phenylbutyl, particularly preferably benzyl;
C6-C14-aryl, for example phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl and 9-phenanthryl, preferably phenyl, 1-naphthyl and 2-naphthyl, particularly preferably phenyl;
C6-C14-aryl such as phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl and 9-phenanthryl, substituted by one or more identical or different substituents selected from among
C1-C8-alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, 1,2-dimethylpropyl, isoamyl, n-hexyl, isohexyl, sec-hexyl, n-heptyl, isoheptyl and n-octyl; preferably C1-C6-alkyl such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, 1,2-dimethylpropyl, isoamyl, n-hexyl, isohexyl, sec-hexyl, particularly preferably C1-C4-alkyl such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and tert-butyl;
examples of substituted C1-C8-alkyl groups are: monohalogenated and polyhalogenated C1-C8-alkyl groups such as fluoromethyl, difluoromethyl, trifluoromethyl, chloromethyl, dichloromethyl, trichloromethyl, bromomethyl, dibromomethyl, tribromomethyl, pentafluoroethyl, perfluoropropyl and perfluorobutyl, particularly preferably fluoromethyl, difluoromethyl, trifluoromethyl and perfluorobutyl;
C3-C12-cycloalkyl such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, cycloundecyl and cyclododecyl; preferably cyclopentyl, cyclohexyl and cycloheptyl;
C7-C13-aralkyl, preferably C7-C12-phenylalkyl such as benzyl, 1-phenethyl, 2-phenethyl, 1-phenylpropyl, 2-phenylpropyl, 3-phenylpropyl, neophyl (1-methyl-1-phenylethyl), 1-phenylbutyl, 2-phenylbutyl, 3-phenylbutyl and 4-phenylbutyl, particularly preferably benzyl;
C6-C14-aryl, for example phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl and 9-phenanthryl, preferably phenyl, 1-naphthyl and 2-naphthyl, particularly preferably phenyl;
halogen, for example fluorine, chlorine, bromine and iodine, particularly preferably fluorine and chlorine;
C1-C6-alkoxy groups such as methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy, n-pentoxy, isopentoxy, n-hexoxy and isohexoxy, particularly preferably methoxy, ethoxy, n-propoxy and n-butoxy;
C6-C14-aryloxy groups such as phenoxy, ortho-cresyloxy, meta-cresyloxy, para-cresyloxy, xcex1-naphthoxy, xcex2-naphthoxy and 9-anthryloxy;
silyl groups SiR18R19R20, where R18 to R20 are selected independently from among hydrogen, C1-C8-alkyl groups, the benzyl group and C6-C14-aryl groups; particular preference is given to the trimethylsilyl, triethylsilyl, triisopropylsilyl, diethylisopropylsilyl, dimethylthexylsilyl, tert-butyldimethylsilyl, tert-butyldiphenylsilyl, tribenzylsilyl, triphenylsilyl and tri-para-xylylsilyl groups; particular preference is given to the trimethylsilyl group and the tert-butyldimethylsilyl group;
silyloxy groups OSiR18R19R20, where R18 to R20 are selected independently from among hydrogen, C1-C8-alkyl groups, the benzyl group and C6-C14-aryl groups; preference is given to the trimethylsilyloxy, triethylsilyloxy, triisopropylsilyloxy, diethylisopropylsilyloxy, dimethylthexylsilyloxy, tert-butyldimethylsilyloxy, tert-butyldiphenylsilyloxy, tribenzylsilyloxy, triphenylsilyloxy and the tri-para-xylylsilyloxy groups; particular preference is given to the trimethylsilyloxy group and the tert-butyldimethylsilyloxy group;
five- to six-membered nitrogen-containing heteroaryl radicals such as for example N-pyrrolyl, pyrrol-2-yl, pyrrol-3-yl, N-imidazolyl, 2-imidazolyl, 4-imidazolyl, 1,2,4-triazol-3-yl, 1,2,4-triazol-4-yl, 2-pyridyl, 3-pyridyl, 4-pyridyl, 3-pyridazinyl, 4-pyridazinyl, 2-pyrimidinyl, 4-pyrimidinyl, 5-pyrimidinyl, N-indolyl and N-carbazolyl;
five- to six-membered nitrogen-containing heteroaryl radicals such as for example N-pyrrolyl, pyrrol-2-yl, pyrrol-3-yl, N-imidazolyl, 2-imidazolyl, 4-imidazolyl, 1,2,4-triazol-3-yl, 1,2,4-triazol-4-yl, 2-pyridyl, 3-pyridyl, 4-pyridyl, 3-pyridazinyl, 4-pyridazinyl, 2-pyrimidinyl, 4-pyrimidinyl, 5-pyrimidinyl, N-indolyl and N-carbazolyl, each bearing one or more identical or different substituents selected from among
C1-C8-alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, 1,2-dimethylpropyl, isoamyl, n-hexyl, isohexyl, sec-hexyl, n-heptyl, isoheptyl and n-octyl; preferably C1-C6-alkyl such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, 1,2-dimethylpropyl, isoamyl, n-hexyl, isohexyl, sec-hexyl, particularly preferably C1-C4-alkyl such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and tert-butyl;
Examples of substituted C1-C8-alkyl groups are: monohalogenated and polyhalogenated C1-C8-alkyl groups such as fluoromethyl, difluoromethyl, trifluoromethyl, chloromethyl, dichloromethyl, trichloromethyl, bromomethyl, dibromomethyl, tribromomethyl, pentafluoroethyl, perfluoropropyl and perfluorobutyl, particularly preferably fluoromethyl, difluoromethyl, trifluoromethyl and perfluorobutyl;
C3-C12-cycloalkyl such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, cycloundecyl and cyclododecyl; preferably cyclopentyl, cyclohexyl and cycloheptyl;
C7-C13-aralkyl, preferably C7-C12-phenylalkyl such as benzyl, 1-phenethyl, 2-phenethyl, 1-phenylpropyl, 2-phenylpropyl, 3-phenylpropyl, neophyl (1-methyl-1-phenylethyl), 1-phenylbutyl, 2-phenylbutyl, 3-phenylbutyl and 4-phenylbutyl, particularly preferably benzyl;
C6-C14-aryl, for example phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl and 9-phenanthryl, preferably phenyl, 1-naphthyl and 2-naphthyl, particularly preferably phenyl;
halogen, for example fluorine, chlorine, bromine and iodine, particularly preferably fluorine and chlorine;
C1-C6-alkoxy groups such as methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy, n-pentoxy, isopentoxy, n-hexoxy and isohexoxy, particularly preferably methoxy, ethoxy, n-propoxy and n-butoxy;
C6-C14-aryloxy groups such as phenoxy, ortho-cresyloxy, meta-cresyloxy, para-cresyloxy, xcex1-naphthoxy, xcex2-naphthoxy and 9-anthryloxy;
silyl groups SiR18R19R20, where R18 to R20 are selected independently from among hydrogen, C1-C8-alkyl groups, the benzyl group and C6-C14-aryl groups; particular preference is given to the trimethylsilyl, triethylsilyl, triisopropylsilyl, diethylisopropylsilyl, dimethylthexylsilyl, tert-butyldimethylsilyl, tert-butyldiphenylsilyl, tribenzylsilyl, triphenylsilyl and tri-para-xylylsilyl groups; particular preference is given to the trimethylsilyl group and the tert-butyldimethylsilyl group;
silyloxy groups OSiR18R19R20, where R18 to R20 are selected independently from among hydrogen, C1-C8-alkyl groups, the benzyl group and C6-C14-aryl groups; preference is given to the trimethylsilyloxy, triethylsilyloxy, triisopropylsilyloxy, diethylisopropylsilyloxy, dimethylthexylsilyloxy, tert-butyldimethylsilyloxy, tert-butyldiphenylsilyloxy, tribenzylsilyloxy, triphenylsilyloxy and the tri-para-xylylsilyloxy groups; particular preference is given to the trimethylsilyloxy group and the tert-butyldimethylsilyloxy group.
In a preferred embodiment, R1 and R2 and also R3 and R4 are identical in pairs and are selected from among tert-butyl and cyclohexyl radicals. In a particularly preferred embodiment, R5 and R6 are identical and are very particularly preferably hydrogen.
In a particular embodiment, R1 and a suitable R2 to R12 together with one or more Ei, where i=1, 2, 3 or 4, may form a saturated or unsaturated 5- to 12-membered ring. In a further particular embodiment, R3 and a suitable R5 to R12 together with one or more Ei, where i=1, 2, 3 or 4, may form a saturated or unsaturated 5- to 12-membered ring. For example, R1 and R5 may together be:
xe2x80x94(CH2)3-(trimethylene), xe2x80x94(CH2)4-(tetramethylene), xe2x80x94(CH2)5-(pentamethylene), xe2x80x94(CH2)6-(hexamethylene), xe2x80x94CH2xe2x80x94CHxe2x95x90CHxe2x80x94, xe2x80x94CH2xe2x80x94CHxe2x95x90CHxe2x80x94CH2xe2x80x94, xe2x80x94CHxe2x95x90CHxe2x80x94CHxe2x95x90CHxe2x80x94, xe2x80x94Oxe2x80x94CH2xe2x80x94Oxe2x80x94, xe2x80x94Oxe2x80x94CHMexe2x80x94Oxe2x80x94, xe2x80x94Oxe2x80x94CHxe2x80x94(C6H5)xe2x80x94Oxe2x80x94, xe2x80x94Oxe2x80x94CH2xe2x80x94CH2xe2x80x94Oxe2x80x94, xe2x80x94Oxe2x80x94CMe2xe2x80x94Oxe2x80x94, xe2x80x94NMexe2x80x94CH2xe2x80x94CH2xe2x80x94NMexe2x80x94, xe2x80x94NMexe2x80x94CH2xe2x80x94NMexe2x80x94 or xe2x80x94Oxe2x80x94SiMe2xe2x80x94Oxe2x80x94 where Mexe2x95x90CH3.
A1 and A3 are selected from among Cxe2x80x94R15, Cxe2x80x94R16, Sixe2x80x94R15, Sixe2x80x94R16 and N, where A1 and A3 may be identical but do not have to be.
A2 is selected from among Cxe2x80x94R17, Sixe2x80x94R17 and N. Here, not more than one Aj, where j=1, 2, 3, is a nitrogen atom.
R13 to R17 are identical or different and are selected from among
hydrogen,
C1-C8-alkyl groups, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, 1,2-dimethylpropyl, isoamyl, n-hexyl, isohexyl, sec-hexyl, n-heptyl, isoheptyl and n-octyl; preferably C1-C6-alkyl such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, 1,2-dimethylpropyl, isoamyl, n-hexyl, isohexyl, sec-hexyl, particularly preferably C1-C4-alkyl such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and tert-butyl;
examples of substituted C1-C8-alkyl groups are: monohalogenated and polyhalogenated C1-C8-alkyl groups such as fluoromethyl, difluoromethyl, trifluoromethyl, chloromethyl, dichloromethyl, trichloromethyl, bromomethyl, dibromomethyl, tribromomethyl, pentafluoroethyl, perfluoropropyl and perfluorobutyl, particularly preferably fluoromethyl, difluoromethyl, trifluoromethyl and perfluorobutyl;
C2-C8-alkenyl having one to 4 isolated or conjugated double bonds, for example vinyl, 1-allyl, 3-allyl, xcfx89-butenyl, xcfx89-pentenyl, xcfx89-hexenyl, 1-cis-buta-1,3-dienyl or 1-cis-hexa-1,5-dienyl.
examples of substituted C2-C8-alkenyl groups are: isopropenyl, 1-isoprenyl, xcex1-styryl, xcex2-styryl, 1-cis-1,2-phenylethenyl or 1-trans-1,2-phenylethenyl.
C3-C12-cycloalkyl such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, cycloundecyl and cyclododecyl; preferably cyclopentyl, cyclohexyl and cycloheptyl;
examples of substituted cycloalkyl groups are: 2-methylcyclopentyl, 3-methylcyclopentyl, cis-2,4-dimethylcyclopentyl, trans-2,4-dimethylcyclopentyl, cis-2,5-dimethylcyclopentyl, trans-2,5-dimethylcyclopentyl, 2,2,5,5-tetramethylcyclopentyl, 2-methylcyclohexyl, 3-methylcyclohexyl, 4-methylcyclohexyl, cis-2,6-dimethylcyclohexyl, trans-2,6-dimethylcyclohexyl, cis-2,6-diisopropylcyclohexyl, trans-2,6-diisopropylcyclohexyl, 2,2,6,6-tetramethylcyclohexyl, 2-methoxycyclopentyl, 2-methoxycyclohexyl, 3-methoxycyclopentyl, 3-methoxycyclohexyl, 2-chlorocyclopentyl, 3-chlorocyclopentyl, 2,4-dichlorocyclopentyl, 2,2,4,4-tetrachlorocyclopentyl, 2-chlorocyclohexyl, 3-chlorocyclohexyl, 4-chlorocyclohexyl, 2,5-dichlorocyclohexyl, 2,2,6,6-tetrachlorocyclohexyl, 2-thiomethylcyclopentyl, 2-thiomethylcyclohexyl, 3-thiomethylcyclopentyl, 3-thiomethylcyclohexyl and further derivatives;
NO2,
halogen selected from among fluorine, chlorine, bromine and iodine, particularly preferably fluorine and chlorine,
C7-C13-aralkyl, preferably C7-C12-phenylalkyl such as benzyl, 1-phenethyl, 2-phenethyl, 1-phenylpropyl, 2-phenylpropyl, 3-phenylpropyl, neophyl (1-methyl-1-phenylethyl), 1-phenylbutyl, 2-phenylbutyl, 3-phenylbutyl and 4-phenylbutyl, particularly preferably benzyl;
C6-C14-aryl, for example phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl and 9-phenanthryl, preferably phenyl, 1-naphthyl and 2-naphthyl, particularly preferably phenyl;
C6-C14-aryl such as phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl and 9-phenanthryl, substituted by one or more identical or different substituents selected from among
C1-C8-alkyl groups, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, 1,2-dimethylpropyl, isoamyl, n-hexyl, isohexyl, sec-hexyl, n-heptyl, isoheptyl and n-octyl; preferably C1-C6-alkyl such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, 1,2-dimethylpropyl, isoamyl, n-hexyl, isohexyl, sec-hexyl, particularly preferably C1-C4-alkyl such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and tert-butyl;
examples of substituted C1-C8-alkyl groups are: monohalogenated and polyhalogenated C1-C8-alkyl groups such as fluoromethyl, difluoromethyl, trifluoromethyl, chloromethyl, dichloromethyl, trichloromethyl, bromomethyl, dibromomethyl, tribromomethyl, pentafluoroethyl, perfluoropropyl and perfluorobutyl, particularly preferably fluoromethyl, difluoromethyl, trifluoromethyl and perfluorobutyl;
C3-C12-cycloalkyl such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, cycloundecyl and cyclododecyl; preferably cyclopentyl, cyclohexyl and cycloheptyl;
C7-C13-aralkyl, preferably C7-C12-phenylalkyl such as benzyl, 1-phenethyl, 2-phenethyl, 1-phenylpropyl, 2-phenylpropyl, 3-phenylpropyl, neophyl (1-methyl-1-phenylethyl), 1-phenylbutyl, 2-phenylbutyl, 3-phenylbutyl and 4-phenylbutyl, particularly preferably benzyl;
C6-C14-aryl, for example phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl and 9-phenanthryl, preferably phenyl, 1-naphthyl and 2-naphthyl, particularly preferably phenyl;
halogen, for example fluorine, chlorine, bromine and iodine, particularly preferably fluorine and chlorine;
C1-C6-alkoxy groups such as methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy, n-pentoxy, isopentoxy, n-hexoxy and isohexoxy, particularly preferably methoxy, ethoxy, n-propoxy and n-butoxy;
C6-C14-aryloxy groups such as phenoxy, ortho-cresyloxy, meta-cresyloxy, para-cresyloxy, xcex1-naphthoxy, xcex2-naphthoxy and 9-anthryloxy;
silyl groups SiR18R19R20, where R18 to R20 are selected independently from among hydrogen, C1-C8-alkyl groups, the benzyl groups and C6-C14-aryl groups; preferably the trimethylsilyl, triethylsilyl, triisopropylsilyl, diethylisopropylsilyl, dimethylthexylsilyl, tert-butyldimethylsilyl, tert-butyldiphenylsilyl, tribenzylsilyl, triphenylsilyl and tri-para-xylylsilyl groups; particularly preferably the trimethylsilyl group and the tert-butyldimethylsilyl group;
silyloxy groups OSiR18R19R20, where R18 to R20 are selected independently from among hydrogen, C1-C8-alkyl groups, the benzyl groups and C6-C14-aryl groups; preferably the trimethylsilyloxy, triethylsilyloxy, triisopropylsilyloxy, diethylisopropylsilyloxy, dimethylthexylsilyloxy, tert-butyldimethylsilyloxy, tert-butyldiphenylsilyloxy, tribenzylsilyloxy, triphenylsilyloxy and the tri-para-xylylsilyloxy groups; particularly preferably the trimethylsilyloxy group and the tert-butyldimethylsilyloxy group;
five- to six-membered nitrogen-containing heteroaryl radicals such as for example N-pyrrolyl, pyrrol-2-yl, pyrrol-3-yl, N-imidazolyl, 2-imidazolyl, 4-imidazolyl, 1,2,4-triazol-3-yl, 1,2,4-triazol-4-yl, 2-pyridyl, 3-pyridyl, 4-pyridyl, 3-pyridazinyl, 4-pyridazinyl, 2-pyrimidinyl, 4-pyrimidinyl, 5-pyrimidinyl, N-indolyl and N-carbazolyl;
five- to six-membered nitrogen-containing heteroaryl radicals such as for example N-pyrrolyl, pyrrol-2-yl, pyrrol-3-yl, N-imidazolyl, 2-imidazolyl, 4-imidazolyl, 1,2,4-triazol-3-yl, 1,2,4-triazol-4-yl, 2-pyridyl, 3-pyridyl, 4-pyridyl, 3-pyridazinyl, 4-pyridazinyl, 2-pyrimidinyl, 4-pyrimidinyl, 5-pyrimidinyl, N-indolyl and N-carbazolyl, each bearing one or more identical or different substituents selected from among
C1-C8-alkyl groups, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, 1,2-dimethylpropyl, isoamyl, n-hexyl, isohexyl, sec-hexyl, n-heptyl, isoheptyl and n-octyl; preferably C1-C6-alkyl such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, 1,2-dimethylpropyl, isoamyl, n-hexyl, isohexyl, sec-hexyl, particularly preferably C1-C4-alkyl such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and tert-butyl;
examples of substituted C1-C8-alkyl groups are: monohalogenated and polyhalogenated C1-C8-alkyl groups such as fluoromethyl, difluoromethyl, trifluoromethyl, chloromethyl, dichloromethyl, trichloromethyl, bromomethyl, dibromomethyl, tribromomethyl, pentafluoroethyl, perfluoropropyl and perfluorobutyl, particularly preferably fluoromethyl, difluoromethyl, trifluoromethyl and perfluorobutyl;
C3-C12-cycloalkyl such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, cycloundecyl and cyclododecyl; preferably cyclopentyl, cyclohexyl and cycloheptyl;
C7-C13-aralkyl, preferably C7-C12-phenylalkyl such as benzyl, 1-phenethyl, 2-phenethyl, 1-phenylpropyl, 2-phenylpropyl, 3-phenylpropyl, neophyl (1-methyl-1-phenylethyl), 1-phenylbutyl, 2-phenylbutyl, 3-phenylbutyl and 4-phenylbutyl, particularly preferably benzyl;
C6-C14-aryl, for example phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl and 9-phenanthryl, preferably phenyl, 1-naphthyl and 2-naphthyl, particularly preferably phenyl;
halogen, for example fluorine, chlorine, bromine and iodine, particularly preferably fluorine and chlorine;
C1-C6-alkoxy groups such as methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy, n-pentoxy, isopentoxy, n-hexoxy and isohexoxy, particularly preferably methoxy, ethoxy, n-propoxy and n-butoxy;
C6-C14-aryloxy groups such as phenoxy, ortho-cresyloxy, meta-cresyloxy, para-cresyloxy, xcex1-naphthoxy, xcex2-naphthoxy and 9-anthryloxy;
silyl groups SiR18R19R20, where R18 to R20 are selected independently from among hydrogen, C1-C8-alkyl groups, the benzyl groups and C6-C14-aryl groups; preferably the trimethylsilyl, triethylsilyl, triisopropylsilyl, diethylisopropylsilyl, dimethylthexylsilyl, tert-butyldimethylsilyl, tert-butyldiphenylsilyl, tribenzylsilyl, triphenylsilyl and tri-para-xylylsilyl groups; particularly preferably the trimethylsilyl group and the tert-butyldimethylsilyl group;
silyloxy groups OSiR18R19R20, where R18 to R20 are selected independently from among hydrogen, C1-C8-alkyl groups, benzyl radicals and C6-C14-aryl groups; preferably the trimethylsilyloxy, triethylsilyloxy, triisopropylsilyloxy, diethylisopropylsilyloxy, dimethylthexylsilyloxy, tert-butyldimethylsilyloxy, tert-butyldiphenylsilyloxy, tribenzylsilyloxy, triphenylsilyloxy and tri-para-xylylsilyloxy groups; particularly preferably the trimethylsilyloxy group and the tert-butyldimethylsilyloxy group.
Here, two radicals R13 to R17 with or without one or more groups Aj may form a saturated or unsaturated 5- to 12-membered ring which may in turn bear substituents. Thus, for example R15 and R17 may together be:
xe2x80x94(CH2)3-(trimethylene), xe2x80x94(CH2)4-(tetramethylene), xe2x80x94(CH2)5-(pentamethylene), xe2x80x94(CH2)6-(hexamethylene), xe2x80x94CH2-CHxe2x95x90CHxe2x80x94, xe2x80x94CH2xe2x80x94CHxe2x95x90CHxe2x80x94CH2xe2x80x94, xe2x80x94CHxe2x95x90CHxe2x80x94CHxe2x95x90CHxe2x80x94, xe2x80x94Oxe2x80x94CH2xe2x80x94Oxe2x80x94, xe2x80x94Oxe2x80x94CHMexe2x80x94Oxe2x80x94, xe2x80x94Oxe2x80x94CHxe2x80x94(C6H5)xe2x80x94Oxe2x80x94, xe2x80x94Oxe2x80x94CH2xe2x80x94CH2xe2x80x94Oxe2x80x94, xe2x80x94Oxe2x80x94CMe2xe2x80x94Oxe2x80x94, xe2x80x94NMexe2x80x94CH2xe2x80x94CH2xe2x80x94NMexe2x80x94, xe2x80x94NMexe2x80x94CH2xe2x80x94NMexe2x80x94 or xe2x80x94Oxe2x80x94SiMe2xe2x80x94Oxe2x80x94 where Mexe2x95x90CH3.
In a very particularly preferred embodiment, A1 and A3 are each Cxe2x80x94R15, R13 and R15 are hydrogen, A2 is Cxe2x80x94R17, and R14 and R17 together form a 1,3-butadiene-1,4-diyl unit which may in turn be substituted by radicals Z1 to Z5 (formula IV). 
In formula IV, Z1 to Z5 are identical or different and are selected from among
hydrogen,
C1-C8-alkyl groups, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, 1,2-dimethylpropyl, isoamyl, n-hexyl, isohexyl, sec-hexyl, n-heptyl, isoheptyl and n-octyl; preferably C1-C6-alkyl such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, 1,2-dimethylpropyl, isoamyl, n-hexyl, isohexyl, sec-hexyl, particularly preferably C1-C4-alkyl such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and tert-butyl;
examples of substituted C1-C8-alkyl groups are: monohalogenated and polyhalogenated C1-C8-alkyl groups such as fluoromethyl, difluoromethyl, trifluoromethyl, chloromethyl, dichloromethyl, trichloromethyl, bromomethyl, dibromomethyl, tribromomethyl, pentafluoroethyl, perfluoropropyl and perfluorobutyl, particularly preferably fluoromethyl, difluoromethyl, trifluoromethyl and perfluorobutyl;
C2-C8-alkenyl having one to 4 isolated or conjugated double bonds, for example vinyl, 1-allyl, 3-allyl, xcfx89-butenyl, xcfx89-pentenyl, xcfx89-hexenyl, 1-cis-buta-1,3-dienyl or 1-cis-hexa-1,5-dienyl;
examples of substituted C2-C8-alkenyl groups are: isopropenyl, 1-isoprenyl, xcex1-styryl, xcex2-styryl, 1-cis-1,2-phenylethenyl or 1-trans-1,2-phenylethenyl;
C3-C12-cycloalkyl such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, cycloundecyl and cyclododecyl; preferably cyclopentyl, cyclohexyl and cycloheptyl;
examples of substituted cycloalkyl groups are: 2-methylcyclopentyl, 3-methylcyclopentyl, cis-2,4-dimethylcyclopentyl, trans-2,4-dimethylcyclopentyl, cis-2,5-dimethylcyclopentyl, trans-2,5-dimethylcyclopentyl, 2,2,5,5-tetramethylcyclopentyl, 2-methylcyclohexyl, 3-methylcyclohexyl, 4-methylcyclohexyl, cis-2,6-dimethylcyclohexyl, trans-2,6-dimethylcyclohexyl, cis-2,6-diisopropylcyclohexyl, trans-2,6-diisopropylcyclohexyl, 2,2,6,6-tetramethylcyclohexyl, 2-methoxycyclopentyl, 2-methoxycyclohexyl, 3-methoxycyclopentyl, 3-methoxycyclohexyl, 2-chlorocyclopentyl, 3-chlorocyclopentyl, 2,4-dichlorocyclopentyl, 2,2,4,4-tetrachlorocyclopentyl, 2-chlorocyclohexyl, 3-chlorocyclohexyl, 4-chlorocyclohexyl, 2,5-dichlorocyclohexyl, 2,2,6,6-tetrachlorocyclohexyl, 2-thiomethylcyclopentyl, 2-thiomethylcyclohexyl, 3-thiomethylcyclopentyl, 3-thiomethylcyclohexyl and further derivatives;
NO2,
halogen selected from among fluorine, chlorine, bromine and iodine, preferably fluorine and chlorine,
C7-C13-aralkyl, preferably C7-C12-phenylalkyl such as benzyl, 1-phenethyl, 2-phenethyl, 1-phenylpropyl, 2-phenylpropyl, 3-phenylpropyl, neophyl (1-methyl-1-phenylethyl), 1-phenylbutyl, 2-phenylbutyl, 3-phenylbutyl and 4-phenylbutyl, particularly preferably benzyl;
C6-C14-aryl, for example phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl and 9-phenanthryl, preferably phenyl, 1-naphthyl and 2-naphthyl, particularly preferably phenyl.
Here, two adjacent radicals Z1 to Z5 together with the phenyl system may form a 5- to 12-membered ring. Thus, for example, Z1 and Z2 or Z2 and Z3 may together be:
xe2x80x94(CH2)3-(trimethylene), xe2x80x94(CH2)4-(tetramethylene), xe2x80x94(CH2)5-(pentamethylene), xe2x80x94(CH2)6-(hexamethylene), xe2x80x94CH2xe2x80x94CHxe2x95x90CHxe2x80x94, xe2x80x94CH2xe2x80x94CHxe2x95x90CHxe2x80x94CH2xe2x80x94, xe2x80x94CHxe2x95x90CHxe2x80x94CHxe2x95x90CHxe2x80x94, xe2x80x94Oxe2x80x94CH2xe2x80x94Oxe2x80x94, xe2x80x94Oxe2x80x94CHMexe2x80x94Oxe2x80x94, xe2x80x94Oxe2x80x94CHxe2x80x94(C6H5)xe2x80x94Oxe2x80x94, xe2x80x94Oxe2x80x94CH2xe2x80x94CH2xe2x80x94Oxe2x80x94, xe2x80x94Oxe2x80x94CMe2xe2x80x94Oxe2x80x94, xe2x80x94NMexe2x80x94CH2xe2x80x94CH2xe2x80x94NMexe2x80x94, xe2x80x94NMexe2x80x94CH2xe2x80x94NMexe2x80x94 or xe2x80x94Oxe2x80x94SiMe2xe2x80x94Oxe2x80x94 where Mexe2x95x90CH3.
Anions [Y]xe2x88x92 which have been found to be useful are weakly coordinating anions as are used in the coordination chemistry of nickel and palladium.
A preferred class of anions is made up by those of the formula [BAr4]xe2x88x92.
Here, Ar are C6-C14-aromatic radicals which may be identical or different and may be substituted by one or more substituents selected from among
halogen, for example fluorine, chlorine, bromine and iodine, preferably fluorine and chlorine and particularly preferably fluorine;
C1-C8-alkyl such as for example methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, 1,2-dimethylpropyl, isoamyl, n-hexyl, isohexyl, sec-hexyl, n-heptyl, isoheptyl and n-octyl; preferably C1-C6-alkyl such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, 1,2-dimethylpropyl, isoamyl, n-hexyl, isohexyl, sec-hexyl, particularly preferably C1-C4-alkyl such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and tert-butyl;
examples of substituted C1-C8-alkyl groups are: monohalogenated and polyhalogenated C1-C8-alkyl groups such as fluoromethyl, difluoromethyl, trifluoromethyl, chloromethyl, dichloromethyl, trichloromethyl, bromomethyl, dibromomethyl, tribromomethyl, pentafluoroethyl, perfluoropropyl and perfluorobutyl, particularly preferably fluoromethyl, difluoromethyl, trifluoromethyl and perfluorobutyl; also xe2x80x94CH2CN;
C6-C14-aryl, for example phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl and 9-phenanthryl, preferably phenyl, 1-naphthyl and 2-naphthyl, particularly preferably phenyl;
examples of substituted C6-C14-aryl groups are: pentafluorophenyl, 2,4,6-trichlorophenyl and 3,5-dicyanophenyl.
Particularly preferred anions [Y]xe2x88x92 are, for example, tetraphenylborate, tetrakisperfluorophenylborate [B(C6F5)4]xe2x88x92 and tetrakis(3,5-bistrifluoromethylphenyl)borate [B(C6H3{CF3}2)4]"".
Further particularly useful anions are BF4xe2x88x92, PF6xe2x88x92, AsF6xe2x88x92, SbF6xe2x88x92, ClO4xe2x88x92, CF3SO3xe2x88x92 or CF3CO2xe2x88x92.
A particular advantage of these particularly useful anions is that they can be used in the form of their acids, while numerous borates are commercially available only as expensive N,N-dimethylanilinium salts.
The process for preparing the metal compound of the present invention advantageously comprises reacting a metal complex of the formula II 
with two equivalents of a compound of the formula III a or at least one equivalent of a compound of the formula III b 
and subsequently adding one equivalent of an acid to eliminate one equivalent of the anion of the compound III.
In formula II, X1 and X2 are identical or different and are selected from among the halogens, for example fluorine, chlorine, bromine and iodine, preferably chlorine and bromine.
In compounds of the formula III a, Mxe2x80x2 is selected from among Li, Na, K, Rb, Cs and MgX3, where X3 is selected from among chlorine, bromine and iodine. In preferred embodiments, Mxe2x80x2 is Li or MgBr or MgCl.
In the compounds of the formula III b, Mxe2x80x3 is selected from among Mg and Ca, with preference being given to Mg.
The preparation of the metal complexes of the formula II is described in EP 0 827 515. Numerous compounds of the formula III a or III b are commercially available or can be prepared by standard methods as described, for example, in Houben-Weyl, Methoden der organischen Chemie, Thieme Verlag Stuttgart, Volumes 13/1 and 13/2a, 1970.
The reaction conditions for the reaction of the metal complexes of the formula II with the compound of the formula III a or III b are not critical per se and can be chosen within wide limits. The order of addition of the reagents is not critical. Suitable reaction temperatures are from xe2x88x9278xc2x0 C. to +125xc2x0 C., preferably from xe2x88x9240xc2x0 C. to room temperature. The reaction can be carried out under atmospheric pressure or under slightly subatmospheric or superatmospheric pressure, with pressures of from 10 mbar to 10 bar being useful. The reaction is preferably carried out at atmospheric pressure.
The compounds of the formulae III a and III b are generally air and moisture sensitive, so that it is appropriate to work in the absence of air and moisture.
It has been found to be useful to carry out the reaction in a diluent. Diluents can be selected from among:
paraffins such as n-pentane, n-hexane, n-heptane, isooctane, cyclohexane and isododecane,
aromatics such as benzene, toluene, ethylbenzene, o-xylene, m-xylene, p-xylene and mixtures of various aromatics;
noncyclic or cyclic ethers such as diethyl ether, diisopropyl ether, di-n-butyl ether, methyl tert-butyl ether, 1,2-dimethoxyethane, diglycol dimethyl ether, tetrahydrofuran, 1,4-dioxane;
sulfolane and HMPA (hexamethylphosphoramide),
and mixtures of the abovementioned diluents. Preferred diluents are n-pentane, n-hexane and diethyl ether.
The diluent can act as solvent or suspension medium.
The intermediate, to which the formula V can be assigned, 
can be isolated and purified, for which purpose the operations known from coordination chemistry, for example extraction, evaporation, precipitation and reprecipitation, crystallization or chromatography, are suitable. This step can be useful, for example, for removing traces of starting material II or metal salts of the formula Mxe2x80x2X1, Mxe2x80x2X2, Mxe2x80x3(X1)2 or Mxe2x80x3X1X2, as are formed depending on whether III a or III b is used.
However, the purification step can also be omitted and IV can be processed further in situ.
According to the present invention, the intermediate IV is then reacted with a derivative of the anion [Y]xe2x88x92. Suitable derivatives are the conjugated Brxc3x8nsted acids HY, also ammonium salts such as [HxNR*4-x], where x is an integer from 1 to 4 and the radicals R* are identical or different and are selected from among C1-C8-alkyl and C6-C14-aryl, with C1-C8-alkyl and C6-C14-aryl being as defined for R1. Further suitable derivatives are the salts of Yxe2x88x92 with oxonium ions. A particularly preferred oxonium ion is [H(OEt2)2]+ where Et=C2H5.
Preference is given to reacting the intermediate IV with a Brxc3x8nsted acid of [Y]xe2x88x92. These acids of the particularly useful ions BF4xe2x88x92, PF6xe2x88x92, AsF6xe2x88x92, SbF6xe2x88x92, ClO4xe2x88x92, CF3SO3xe2x88x92 or CF3CO2xe2x88x92 can be purchased at low cost.
The reaction conditions are generally not critical. The order of addition of the reactants plays no significant role either with regard to purity or with regard to the yield. Suitable reaction temperatures are from xe2x88x9295xc2x0 C. to +125xc2x0 C., preferably from xe2x88x9240xc2x0 C. to room temperature. The reaction can be carried out under atmospheric pressure, but also under slightly subatmospheric or superatmospheric pressure, with pressures of from 10 mbar to 10 bar being useful. The reaction is preferably carried out at atmospheric pressure.
The novel, generally ionic metal compounds of the formula I can be isolated from the reaction mixtures by operations with which those skilled in the art are familiar, for example extraction, evaporation, precipitation and reprecipitation or crystallization, and can be purified further if necessary. They are generally obtained in good purity and can be used immediately for polymerization. However, owing to their insensitivity to air and moisture, they can also be stored for weeks without special precautions and can then be used without a drop in activity.
The complexes of the present invention can be used directly without further activators for the polymerization or copolymerization of olefins. It is possible to use one or more different metal compounds according to the present invention simultaneously.
Pressure and temperature conditions during the polymerization can be chosen within wide limits. As regards the pressure, a range from 0.5 bar to 4000 bar has been found to be suitable; preference is given to from 10 to 75 bar or high-pressure conditions of from 500 to 2500 bar. As regards temperature, a range from from 0 to 120xc2x0 C. has been found to be suitable; preference is given to from 40 to 100xc2x0 C., particularly preferably from 50 to 85xc2x0 C.
As monomers, mention may be made of the following olefins: ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene or 1-undecene, with particular preference being given to ethylene.
The suitable comonomers include xcex1-olefins, for example from 0.1 to 20 mol % of 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene or 1-undecene. Further suitable comonomers are isobutene and styrene, also internal olefins such as cyclopentene, cyclohexen, norbornene and norbornadiene.
Solvents which have been found to be useful are toluene, ortho-xylene, meta-xylene, para-xylene and ethylbenzene and mixtures of these, also diethyl ether, tetrahydrofuran, chlorobenzene, 1,3-dichlorobenzene, dichloromethane and, under high-pressure conditions, supercritical ethylene.
The polymerization catalyzed by the metal compounds of the present invention can be regulated by means of hydrogen, i.e. the molecular weight of the polymers obtainable by means of the catalyst system of the present invention can be lowered by addition of hydrogen. If sufficient hydrogen is added, waxes are obtained; the hydrogen concentration required also depends on the type of polymerization plant used.
For the metal compounds of the present invention to be able to be used in modern polymerization processes such as suspension processes, bulk polymerization processes or gas-phase processes, it is necessary for them to be immobilized on a solid support. Otherwise, polymer morphology problems (lumps, deposits on walls, blockages in lines or heat exchangers) can result and force shutdown of the plant. Such an immobilized metal compound is referred to as a catalyst.
It has been found that the metal compounds of the present invention can be readily deposited on a solid support. Suitable support materials are, for example, porous metal oxides of metals of groups 2 to 14 or mixtures of these, also sheet silicates and zeolites. Preferred examples of metal oxides of groups 2 to 14 are SiO2, B2O3, Al2O3, MgO, CaO and ZnO. Preferred sheet silicates are montmorillonites or bentonites; as zeolite, preference is given to using MCM-41.
Particularly preferred support materials are spherical silica gels and aluminosilicate gels of the formula SiO2.a Al2O3, where a is generally in the range from 0 to 2, preferably from 0 to 0.5. Such silica gels are commercially available, e.g. Silica Gel SG 332, Sylopol(copyright) 948 or 952 or S 2101 from W. R. Grace or ES 70X from Crosfield.
As particle size of the support material, mean particle diameters of from 1 to 300 xcexcm have been found to be useful; preference is given to from 20 to 80 xcexcm. These particle diameters are determined by known methods such as sieve methods. The pore volume of these supports is from 1.0 to 3.0 ml/g, preferably from 1.6 to 2.2 ml/g and particularly preferably from 1.7 to 1.9 ml/g. The BET surface area is from 200 to 750 m2/g, preferably from 250 to 400 m2/g.
To free the support material of adhering impurities, in particular moisture, the support materials can be baked prior to doping, with temperatures of from 45 to 1000xc2x0 C. being suitable. Temperatures of from 100 to 750xc2x0 C. are particuarly useful for silica gels and other metal oxides. This baking can be carried out for a period of from 0.5 to 24 hours, preferably from 1 to 12 hours. The pressure conditions depend on the method chosen; baking can be carried out in a fixed-bed process, in a stirred vessel or else in a fluidized-bed process. Baking can quite generally be carried out at atmospheric pressure. However, reduced pressures of from 0.1 to 500 mbar are advantageous; a range from 1 to 100 mbar is particularly advantageous and a range from 2 to 20 mbar is very particularly advantageous. On the other hand, it is advisable to carry out a fluidized-bed process under slightly superatmospheric pressure in the range from 1.01 bar to 5 bar, preferably from 1.1 to 1.5 bar.
Chemical pretreatment of the support material with an alkyl compound such as an aluminum alkyl, a lithium alkyl or an aluminoxane is likewise possible.
However, owing to the low sensitivity of the metal compounds of the present invention toward Lewis bases, baking and chemical pretreatment of the support material can be omitted.
A polymerization by the suspension method is carried out using suspension media in which the desired polymer is insoluble or only slightly soluble, because otherwise deposits of product occur in the parts of the plant in which the product is separated from the suspension medium and force repeated shutdowns and cleaning operations. Suitable suspension media are saturated hydrocarbons such as propane, n-butane, isobutane, n-pentane, isopentane, n-hexane, isohexane and cyclohexane, with preference being given to isobutane.
Pressure and temperature conditions during the polymerization can be chosen within wide limits. As regards pressure, a range from 0.5 bar to 150 bar has been found to be useful; preference is given to from 10 to 75 bar. As regards temperature, a range from 0 to 120xc2x0 C. has been found to be useful; preference is given to from 40 to 100xc2x0 C.
As monomers, mention may be made of the following olefins: ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene and 1-undecene.
Suitable comonomers include xcex1-olefins, for example from 0.1 to 20 mol % of 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene and 1-undecene. Further suitable comonomers are isobutene and styrene, also internal olefins such as cyclopentene, cyclohexene, norbornene and norbornadiene.
Furthermore, the catalysts of the present invention have been found to be hydrogen-regulatable, i.e. the molecular weight of the polymers obtainable by means of the catalysts of the present invention can be lowered by addition of hydrogen. If sufficient hydrogen is added, waxes are obtained; the hydrogen concentration required also depends on the type of polymerization plant used. Addition of hydrogen increases the activity of the catalysts of the present invention.
The catalysts of the present invention can also be used together with one or more other polymerization catalysts known per se. Thus, they can be used together with
Ziegler-Natta catalysts,
supported metallocene catalysts of transition metals of groups IV to VI of the Periodic Table of the Elements,
catalysts comprising late transition metals (WO 96/23010),
Fe or Co complexes containing pyridyldiimine ligands, as are disclosed in WO 98/27124,
or chromium oxide catalysts of the Phillips type.
It is possible to mix various catalysts with one another and to introduce them into the polymerization vessel together or to use cosupported complexes on a common support or else to introduce different catalysts separately into the polymerization vessel at the same point or at different points.
The invention is illustrated below by means of working examples.
General remarks: the syntheses and purification operations were, unless indicated otherwise, carried out under strict exclusion of air and moisture. All solvents were dried by standard methods immediately before use (as described, for example, in Organikum, 3rd reprint of the 15th edition, VEB Deutscher Verlag der Wissenschaften, Leipzig 1984). The melting points are not corrected. The 1H-NMR spectra were measured using tetramethylsilane as internal standard.
The starting materials and reagents listed below were prepared by literature methods or purchased:
(xcex72-trans-stilbene)[{(bis(di-t-butylphosphino)]methane-xcexa2P} nickel(0)] as described in EP-A 0 827 515 or by a method analogous to that described by P. Hofmann et al., Z. Naturforsch. 1990, 45b, 897 and DE-A 40 34 604;
bis(dicyclohexylphosphino)methane: F. I. Joslin et al., Polyhedron 1991, 10, 1713 and J. S. Yu, I. P. Rothwell, J. Chem. Soc., Chem. Commun., 1992, 632.
The following abbreviations are employed: Mexe2x95x90CH3; Etxe2x95x90C2H5, Phxe2x95x90C6H5; PE=polyethylene.
1M PhCH2MgCl (benzylmagnesium chloride) in diethyl ether was purchased from Aldrich;
[H(OEt2)2] [B(C6H3{CF3}2)4] was synthesized by the literature method of M. Brookhart et al., Organometallics 1992, 11, 3920.